Twenty-one of the fittest cities in the nation offer 34 superb ways to celebrate your fitness this year.

If you race IRONMAN or IRONMAN 70.3 races or Rock ‘n’ Roll events, there’s a good chance you are doing it in one of the fittest cities in the United States.

This month, the American College of Sports Medicine (ACSM) released its annual American Fitness Index, a ranking of the 100 largest U.S. cities by data related to healthy behaviors, chronic diseases, and community infrastructure. Twenty-one cities and neighboring areas, including six out of the ranking’s top 10, together are home to 34 IRONMAN and IRONMAN 70.3 races and Rock ‘n’ Roll marathons and half marathons.

A sports medicine and exercise science organization, ACSM crunched numbers from "reliable, publicly-accessible and up-to-date sources" to create over 30 indicators of personal and community health. Those indicators ranged from the percentage of the population with high blood pressure to the number of swimming pools per 100,000 residents. A few highlights:

The top 10 cities in walkability ranking include five that host Rock ‘n’ Roll running events: San Francisco, Philadelphia, Chicago, Washington, DC, and Seattle.

Madison teems with healthy people year-round, not just during IRONMAN and IRONMAN 70.3 weekends: Madison ranked #4 overall and had the highest percentage (74%) of residents getting at least seven hours of sleep nightly.

At #9 overall, San Jose came out on top for the personal health ranking.

Below are the 21 cities, organized by their overall ranking out of 100, followed by the races on offer there. Registration is still open for many races, so check out the links and get racing!